The partially resolved rotational contour of one member of the strong Rydberg series of butadiene was analyzed. The absorption band was demonstrated to arise from the predicted 'Au yields 'Ag transition. The ultraviolet absorption spectra of (SiH3)2S, (GeH3)2S, (Si(CH3)3)2S and (C(CH3)3)2S were recorded from 2300-1200 A. These and the published spectra of other symmetrically substituted sulfides were collectively analyzed. Some of the published assignments of H2S, (CH3)2S, and (C(CH3)3)2S are revised. The absorption spectra of cis and trans-difluoroethylene and their perdeuterated isomers were measured between 1200 and 1650A. The spectrum of each molecule is analyzed into several Rydberg series to the lowest ionization potential, and the 3s-Rydberg transition to the second ionization potential of the trans-molecule. The d-Rydberg series in each molecule is deduced to be a ddelta-series to the bg orbital in trans-difluoroethylene and to the ag orbital in cis-difluoroethylene.